<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>v-on</title>
</head>
<body>
<div id="app">

  <button @click="fn2(event)">点击</button>
</div>
<script src="https://cdn.jsdelivr.net/npm/vue@2.5.21/dist/vue.min.js"></script>
<script>
  let vm = new Vue({
    el: "#app",
    methods:{
      fn1: function (e){
        console.log(e)
      },
      fn2: function (){
        console.log(event)
      }
    }
  })
</script>
</body>
</html>